[IMP] theme_clean: update the theme

This commit updates the theme to improve the design with new colors, new
pictures and new snippet customizations.

task-2597387

Part-of: odoo/design-themes#500

theme_clean/views/snippets/s_numbers.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+<template id="s_numbers" inherit_id="website.s_numbers">
+    <!-- Section -->
+    <xpath expr="//section" position="attributes">
+        <attribute name="class" add="o_cc4 pt64" remove="o_cc2 pt24" separator=" "/>
+        <attribute name="data-oe-shape-data">{"shape":"web_editor/Airy/10","flip":[]}</attribute>
+    </xpath>
+    <!-- Shape -->
+    <xpath expr="//div[hasclass('container')]" position="before">
+        <div class="o_we_shape o_web_editor_Airy_10"/>
+    </xpath>
+</template>
+
+</odoo>